The control of invertebrate pests such as arthropods is extremely important in achieving high crop efficiency. Damage by invertebrate pests to growing and stored agronomic crops can cause significant reduction in productivity and thereby result in increased costs to the consumer. The control of invertebrate pests in forestry, greenhouse crops, ornamentals and nursery crops is also important.
Plants are subject to injury by invertebrate pests at all stages of growth, beginning with seeds or other propagules such as bulbs, tubers, rhizomes, corms, and stem and leaf cuttings and ending with mature plants. Besides the cost of materials, the effort and time required for application of invertebrate pest control substances make repetition of treatments undesirable. Ideally a single treatment of a plant at the propagule stage would protect the plant from invertebrate pests during its entire life.
A variety of techniques for treating propagules with plant protection substances are known. These include soaking propagules in arthropodicide-comprising solutions, coating propagules with films, pelleting materials and the like comprising arthropodicidal compositions, and applying arthropodicidal compounds to the growing medium surrounding the propagules. While some compounds can effectively protect propagules from certain phytophagous invertebrate pests, new compounds are needed that are more effective or have a broader spectrum of activity, are less costly, less toxic, environmentally safer or have different modes of action.
Particularly needed are invertebrate pest control treatments that can protect the plant not only at its propagule stage but also later in its development. Achieving this objective requires compounds that are active against invertebrate pests and can effectively translocate from the locus of the propagule up through the growing stems, leaves and other aboveground plant parts. Furthermore the compounds need to have high activity against invertebrate pests to compensate for the dilution occasioned by the expanding plant mass. Also, the compounds cannot rapidly degrade and lose their biological potency in the environment of the plant's vascular tissues. The combination of these properties is rare. Treatments of propagules effective for protecting from phytophagous invertebrate pests not only the propagule but also the plant at later growth stages have now been discovered.